Brush of high bristle density



I, Feb. 25, 195s FIG. Il

w. c. VAN cLlEF, JR 2,824,327

BRUSH 0F HIGH BRISTLE DENSITY 3 Sheets-Shee'kl 1 Feb. 25, 1958 w. c. VAN cLlEF, JR 2,824,327

BRUSH OF'HIGH BRISTLE DENSITY 3 She'ets-Sheet 2 Filed OCT.. 11, 1954 FIG'.I3

FIC ,6

FIG.5

Anne/va' Feb. 25, 1958 w. c. VAN cLlEF, JR 2,824,327

BRUSH OF HIGH BRISTLE DENSITY Filed oct. 11, 1954v 3 sheets-Sheet s Flc.. 7 l maa United States Patent VC )tlice v 2,824,327 Patented Feb. 25., 1958 BRUSH oF HIGH BRISTLE DENSITY William C. Van Clief, Jr., Baltimore, Md., assignor to Pittsburgh Plate Glass Company, Allegheny County, Pa., a corporation of Pennsylvania Application October 11,1954, Serial No. 461,302

7 Claims. (Cl. 15-181) This invention relates to a rotary cylindrical brush and it has particular relation to a power-driven brush having an exceptionally high count of bristles per unit area.

Rotary cylindrical, power-driven brushes suitable for various scrubbing and brushing operations have heretofore been formed by a number of different methods such (A) by spirally winding brush strips comprising channels crimped about the butts of double ended bristles, which bristles are in turn looped, or replicately folded about iilamentary cores that key the bristles in the channels; and

(B) by stacking annular laminae or basic sections concentrically upon a supporting core.

ln the formation of the laminae or basic units, it is customary to secure double ended bristles by replicately bending them about a retaining ring and by axially compressing the sides of the bristles between a pair of spaced annular rings or discs, which are appropriately held together upon the bristles by an eyelet-like structure or by some other type of interconnection that can not readily be compressed.

In either of the foregoing methods of forming cylindrical power-driven brushes, it will be manifest that considerable bodies of metal are interposed at intervals between portions of the bristles. For example, where the brush is formed by spirally winding a channel strip upon a core or mandrel, it will be obvious that the sides of the channel strip constitute such body and this metal, of necessity, must replace considerable numbers of bristles, thus materially reducing the bristle count per given unit of brush surface. The reduction in the bristle count, of course, reduces the overall stiffness of the brush, thus permitting a high degree of flexing of the bristles during brushing operations, imposing a heavy load upon the bristle units and otherwise producing effects which impair the efciency or shorten the length of life of ,a given brush unit.

press the bristle material by application of longitudinal pressure upon the assembly, without actually distorting the metallic structures employed to retain the bristles. The diiiculty in thus axially compressing the strips or laminations upon a core, constitutes another reason for reduced bristle count per unit area in the resultant brushes.

In either of Vthe conventional types of power-driven brush structures the loss of a few bristles at a given point will tend to loosen the pressure on contiguouskbristles, theyy in turn, may be lost and the disintegrating action can progress chainlike along the entire spiral or about the entire base section. In the event the brush is formed of annular sections, breakdown of a section will loosen the longitudinal pressure on the entire stack. s

In accordance with one feature, the present invention comprises a rotary cylindrical brush structure which is assembled from laminae which are strung upon a retaining core without the interposition of the metallic separators of the conventional laminar brush between 1aminae and without the use of metallic channels of a spirally wound brush. Y In accordance with the provisions of this invention, the laminae are assembled only with retaining rings in the looped portions of the bristles and the laminae are held from axial displacement by a pair of annular rings which are locked directly to the ends of the brush core.

As a further feature, the invention comprises the pro vision of one' or more radially projecting longitudinal fins upon a core of a cylindrical rotary brush, which fins are common to all of the laminae or sections and act as seats for the retaining rings for the looped doubleV ended bristles, provide means securing the brush laminae from creeping peripherally as Vthe brush rotates and which assist in limiting progressive loosening and shedding of bristles from a row, or unit, in event that a small number of bristles should be lost from a localized area.

As a still further feature, the invention comprises the provision ofl a tubular brush bristle core in which the ends of the core are castellated so that they can conveniently be bent over to clamp annular end retaining rings upon the core and the cutaway portions of the metal in the castellations provide detents meshing with the castellations of a contiguous unit, in event that a plurality of brushes are strung organged together upon y a common mandrel. All of these features need not necessarily be associated in each brush.

This is especially true in those instances where the brush is employed for scrubbing sheet metal, as for instance as a preliminary operation in the galvanizing of sheet metal with molten zinc. This is often a heavy-duty operation and the brushes employed therein are subjected to heavy wear.

In similar manner, in brushes assembled from annular sections or laminae, the rings employed between the units of laminations, of necessity', must replace considerable amounts of bristle stock. The lives of cylindrical brushes assembled from such laminations, of necessity, is shortened by this reduction of bristle material. Needless to say, the metal employed in either type of conventional brush is expensive and the cost thereof must be imposed upon the purchaser.

It may also be pointed out that where a cylindrical brush is formed by helically winding a channel strip upon a core or by assembling a series of preformed laminations involving rigidly held discs or annular rings, it is dicult,

or impossible substantially axially to compact or com- For a better understanding of the principles of the in-` vention, reference may now be had to the accompanying drawings in which like numerals refer to like parts throughout.

In the drawings: v

Fig. 1 is a sectional View illustrating the construction of a brush formed in accordance with the present inven tion; Fig. 2 is an end view of the construction shown in Fig. l;

Fig. 3 is aview partially in elevation and partially section of the Icore structure of the brush; `Y

Fig. 4 is a plan view of the construction shown in Fig. 3;

Figs. 5 and 6 are sectional views of brush;

Fig. 7 is a sectional view of a still further form of the brush; f

Fig. 8 is an end view of the brush shown in Fig. 7;

Fig. 9 is a sectional view of a gang of brush units on a common mandrel;

of modified forms Fig. 10 is a face view of 'a clamping plate for the Fig. 12 is a fragmentary section of a further modified form of brush; and

Fig. 13 is a diagrammatical view illustrating the direction of forces acting upon the bristles to clamp them in position upon the brush core.

A brush constructed in accordance with this invention comprises a core 19, which includes sidewalls 20 of sheet metal and radially extending longitudinal tins 21, which are formed by replieately folding narrow longitudinally extending sections of the metal constituting the tubular walls 20. Any number of ns desired may be provided but for purposes of illustration eight are shown. These may be evenly spaced so that they assist in centering the retaining `rings with respect to the core. Within the core are disposed a plurality of bushings 22 each of which comprises a web portion 23 and edge flanges 24 and 26 extending axially but in opposite direction with respect to each other. The outer of the flanges 26 may be secured in position in the tubular core -by appropriate means as for example by spot welding at such points as are indicated at 27. The intervals between points of welding may be spaced in accordance with the strength of the bond required to resist shear between the bushing and the wall to which it is attached.

As many bushings may be included in the construction `as are desired, though of course it is preferable that a bushing be located at, or contiguous to, each end of the core. As illustrated in Fig. 4 of the drawings, the bushings are provided with keyways 28, adapted to receive keys (not shown) by means of which they are locked against rotation on the mandrel. In some instances, itmay be preferable to key the bushings upon the mandrel by forming the bushings with other appropriate noncircular shapes of center openings. For example, the openings may be hexagonal or octagonal in which event the keyway 28 is not required. The ends of the cores are formed with cutout portions 29 providing castellation 30, shown in Fig. 3. In forming the castellations, suicient metals should be cut out at 29 to assure that the castellations of contiguous units will intermesh with each other` to provide a clutch-like coupling in event that two or more of the units are strung together upon a common mandrel.

The radial width of the tins 21 on the cylindrical core preferably approximately corresponds -to the thickness of the layer of the bristles in lamination A at their mid portions. The bristles are of the double ended type and are looped about wire retaining rings 31 which in the embodiment of the invention shown, comprise cylindrical wires of appropriate gauge having end portions welded together or otherwise joined to provide a continuous, solid ring one of which is provided for each of the laminations. The rings in the embodiment of the invention shown in Fig. 1 are of a diameter corresponding approximately to the circle of the diameters of the tip portions of the tins 21. Indeed the rings may seat directly upon the ins but may be of slightly greater diameter if so desired. The laminae of desired thickness, are assembled in as many layers as are required to till the tubular core and may be tightly compacted one upon the other as hereinafter described. It will be observed that the waist portions of all or many of the bristles, which Aare looped about the retaining rings 31, lie within the spaces between tins 21 so that they are retained from rotation or creeping about the circumference of the brush. Also, if a small tuft of bristles should be lost in any given locality and a resultant tendency for contiguous bristle to loosen and become lost in progression around the circumference of the 'brush is set up,'the ns act as limiting barriers which check the progress of the loosening action and thus greatly prolong the length of life of the brush in actual service. t However, the amount of metal in the tins is but small and very few bristles are replaced thereby.

While the tins 21 are, for the. foregoing reaSOnS,

deemed to be quite desirable to the attainment of the full advantages of the present invention, it will be evident that some of the advantages can be attained without the use thereof, in as much as the bristles could be retained from peripheral creeping about the circumference of the brush by use of a cement, binding the waists of the bristles to the core, or by other means.

The laminae are held in position from axial displacement by means of suitable end retaining elements, such as annular rings 32 and 32a. These rings tit over the castellations 30 of the tubular core 20 Vand seat upon the ends of the ilanges 21. The castellations are bent over as at 33 to maintain them in the desired position.

It will be apparent that each tin is radially disposed with respect to the core or tube 26. lf desired, each core may be made up of two or more sections, the ends of which are joined by welding or by folding to provide longitudinally extending seams. The joints may be overlapped and welded or they may merely be butted together and welded to provide a smooth continuous surface as indicated for example at joint l1. Other points in the circumference of the tube, such as J2, J3 or I4, may also be selected as the lines of union. Fig. l1 illustrates a modified joint in which one edge of a core blank is folded approximately to an inverted U (as indicated at U) and the contiguous edge of the same or a neigh boring blank is bent radially outwardly as at U2 and is clamped between the legs of the U. The iins thus function both as ns and as a union between contiguous edges. If desired, the tubular cores 20 may be formed of a single sheet in which instance but a single line of union is required in order to join the two ends of the blank.

Bushings 22 for insertion in the tubular core, in the manner illustrated in Figs. 3 and 4 of the drawings, are formed as separate units by conventional means which it is not deemed necessary to describe in this appiication. These units are inserted in the tubular core and held in place by spot welding as indicated at 27.

In the assembly of a brush, it is desirable that annular end ring 32 be positioned upon the tubular core and the castellations 3? be bent over to retain it in position against the ends of the hns 21, whereby to facilitate subsequent assembling of the brush structure. A brush embodying the principles of the invention may be assembled manually or by application of various embodiments of apparatus.

A more detailed description of the specific apparatus will be found in my copending application entitled Method of and Apparatus For Forming Rotary Brush, Serial Number 461,303.

ln Fig. 5 of the drawing is illustrated a modified form of brush construction in which retaining rings of n plurality of dierent diameters are employed in the 1arninations. The several laminae are stacked in alternation, first a lamination A having a ring of smaller, internal diameter, and then one A1 of larger internal diameter. In this construction, the retaining ring 31 of smaller internal diameter is disposed upon or near the outer edges of the tins 21. Owing to the doubling of the bristles at their mid portions and also owing to the presence of the metallic ring about which the mid portions are looped, a substantially thickened roll indicated at R in Fig. 5 is formed and this roll would inherently tend somewhat to reduce the average density per unit area of the brush bristles. Where a second ring 31a of larger diameter is employed, the thickened roll is disposed at or slightly beyond the outer diameter of bulge of the lamination containing the ring of smaller diameter. The spacing between the laminations along the longitudinal axis of the brush can thus be appreciably reduced whereby to increase the bristle density per unit area of the brush construction.

The intermeshing of the bristles of the laminations A, with those of A1 prevent them from creeping. it desired, as shown in Fig. 12, the bristles about cores or aangaan rings-31a may beomitted. vThe latter then'tend to corn-,

press and more firmly to hold the bristles in the contiguy. ous laminae. Since they are outside of the perimeter. of the rings 31 they do not reduce the number of bristles: which may be assembled in the brush. If preferred, rings 31a may comprise annular stampings having axially projecting teeth designed to pierce the laminae.

' As a further feature as illustrated in Figs. 12 and 13, cement may be injected at the looped portions of the bristles, as at 145, more securely cementing them to the core walls 20 and also acting as a medium preventing accumulation of scrubbing uids, such as aqueous acids between said Walls and the looped portions of the bristles. The directions of the forces acting on the looped portions 4of the bristles to clamp them against the core Walls and between the several rings are illustrated in Fig. 13. y.

` In the-construction as shown in Figs. 7 and 8 the use of bushings 22 in the ends of the core wall 20 is obviated. In this construction, end rings 32' and 32a are replaced by rings 150, are formed to an internal diameter corresponding to the internal diameter of the bushings. A series of properly spaced slots v151 disposed in a circle corresponding to the diameter of the tube 19 receive the castellations 30 and in the nished brush are clinched outwardly to retain the rings. The end rings slip over a mandrel and thus permit the latter to be eliminated. The steps of forming a brush by use of such construction are essentially the same as those previously described.

While emphasis has been placed upon the use of end rings 32 and 32a for clamping the bristle laminations on the core, it is also contemplated, if desired, to spin or otherwise toiiare the ends of the core outwardly without the end rings, in order to retain the laminations in place. With such construction, the notching of the tube 19 to form castellations 30 is not necessary, since the solid metal better retains the bristles.

Brushes constructed in accordance with the provisions of this invention are relatively simple. The tubular core is quite inexpensive, but at the same time, it is of high mechanical strength. This strength is greatly enhanced by the radially projecting ns 21 and also by the bushings 22 which are spot welded into the tubular core. A minimum of metal is required in securing the roots or butt portions of the bristles in place upon the core, which fact as already elaborated upon, is conducive to attainment of very high brush density per unit of area of surface. AThe reduction-in the amount of metal inherently reduces the costs of the construction and the high density of bristle population increases the stiffness of the brush so that it becomes a substantially better means for brushing r scrubbing surfaces and notably of sheet iron or steel preparatory to the galvanizing operation. The stif ne'ssof the brush bristles attained by tightly compacting the bristles of course reduces flexing in brushingoperations and. thus assists in attainment of a longer brush life. As previously pointed out, small vfailures of bristles when they occur, are localized by the tins 21 andprogres# sive failure from the initial points until the entire brush has broken down is prevented, or delayed. It will be apparent that in this construction, the use of tabs or teeth struck out from metal such as thatof an annular disc and having sharp angles and corners likelyto cut or chafe the bristles or to provide points of stress concentration when the bristles ane exed, is obviated.

It is to be noted that the lugs at the ends of the brush cores produced by bending over the castellations 30 to secure the annular end rings 32 and 32a are designed to intermesh in clutch-like engagement. A plurality of brushes can thus be ganged together upon a single or common. mandrel and a driving connection from oe brush to the next can be so attainedzwithout the provision of keyways orotlier holding means extending the e'nti'r'e .length of the mandrel.

"While' the embodiment of the invention described in whichftheg bristles of the brush yarel looped about co'n tinuous retaining rings -31 to form-individual laminations has important advantages and is usually preferred, it will lbe apparent that sometimes the `rings canbe replaced by a continuous filament spirally wound on a core` to retain the bristles. Such construction is shown in Fig. 6.

In the latter, tube 19 has castellations 30 bent over to hold end rings 32. A retaining wire l31b which is spirally wound about the core and rests on ns 21, has an end appropriately secured to the core as for instance by eyelet portion 31e which is secured to tube 20 by a rivet 31d. The other end of the wire may be similarly secured. Bristles are looped about the wire as in the previously described construction to provide a rotary brush in which the bristles are locked from creeping by iins 21. Theiins also function to localize degeneration due to loosening of the row, in event a few bristles should be lost from a given spot.

In'Figs. 8 and 9 is illustrated'a brush involving aseries of units assembled as previously described and being ganged upon a common mandrel and driven through clamping plate 156 and/or 157. An many units as may be desired may be strung together but for purposes of illustration a pair are shown. The castellations 30 at contiguous ends of these, are intermeshed to provide a positive drive. It is a feature of this construction that the intermeshed castellations have a thickness of the walls of the tube 20. The ends of the brush units are thus quite closely juxtaposed and a minimum gap in the bristle surface is provided.

. Clamping plate 156 is removably mounted to permit the insertion of the mandrel in the brush core. To this end a portion of the mandrel is threaded as indicated at 158 to receive a clamping nut 159 which can be turned to tighten it against plate 156 and force it against the contiguous brush unit. The second clamping plate 157 may be similarly mounted, or it may be fixed on the mandrel as by Welding. One or both platesl may be provided with face slots 161 adapted to mesh with clinched over castellations 30. If but one of the plates 156- 157 is provided with slots, it will be apparent that a drive between the driven brush unit and its neighbor is provided by the intermeshing castellations between the two. If three or more units are ganged, the intermediate unit or units are driven from one or both of the end units.

, If the end plate 156 is employed as a driving device for the units on shaft 155, means such as a key 162 in the shaft and the plate should be provided.

It will be observed that shaft 155 is provided with bearing portions 163, which preferably are somewhat smaller in diameter than the threaded portion 158 and the midportionV of the shaft in order to facilitate attachment of endvplate 156 and nut 159. 7 v

In the construction shown in Figs. 9` and l0, the mani drel may be of circular section, as-rnayZ the bushings irrv the brush units since power is transmitted to the brush" units through the end castellations. Y

The forms of the invention as herein illustrated while they constitute as of the present preferred embodiments, are but illustrative of the'inventon. It will be appar-ent to those skilled in the art that various modifications mayr` be made therein without departure from the spirit of the. invention or the scope of the appended claims.

I claim:

1. A rotary brush comprising a substantially cylindrical core having a series of peripherally spaced, longitudinal ns, a series of brush sections disposed upon the core, each section comprising a'retaining ring disposed upon the tins, double ended brushv bristles having their tip portions projecting radially outwardly and hav# ing their mid portions looped about the retaining ring tofo'rm an annular bristle lamination in which the outer bristles of the lamination contact with the corresponding.

'7 bristles @contiguous lan'nnaticunr substantially/'from their looped portidns` to their` tips, the looped portions of thebris'tles of each annular lamination being disposed be` tween the'tns and being groupedf by-I the tins into segments extending peripherally of the corresponding ring, the looped portions of the bristles inthe ends of the segments being in direct contact with a side of each of the two contig'uo'usns', whereby to prevent peripheral creeping of the bristles abouti the core.

2. A rotary! brush comprising a substantially cylindric'al c`ore` having' a series of peripherally spaced, longitudinal tins, a' series of brush sections disposed upon the core, each section comprising a retaining ring disposed upon the tins,A double ended'l brush bristles having their tip portions projecting radially outwardly and `having their mid portions loopedV about the retaining ring to form an annular bristlelarnination. in which the outer bristles of the lamination Contact. with the corresponding bristles of contiguous laminations substantially from their looped portions t'o their tips,A the looped portions of the bristles of each annular lamination being disposed between the ns' and! being grouped by the ns into segments extending peripherally of the corresponding ring, the looped portions of the bristlesv in theV ends of the segments being in direct contact with a side of each of the two contiguous tins, whereby to prevent peripheral creeping of the bristles about the core and annular end plates secured upon the core to prevent longitudinal displacement of the larninations.A

3. A rotary brush comprising a substantially cylindrical tubular core having a series of peripherally spaced longitudinal tins', a seriesV of brush sections disposed upon the core, each section comprising a retaining ring, disposed upon the ns, double ended brush bristles having their tip portions projecting radially outwardly and their mid portions looped about the retaining ring to form an annular bristle lamination in which the outer bristles of the lamination contact with corresponding bristles of contiguous laminations substantially from their looped portions to their tips, the looped portions of the bristles of eachl annular lamination being disposed between the ns and being grouped by the tins into segments extending peripherally of the corresponding ring, the looped portions of thev bristles in the ends of the segments being in direct contact with af side of each of the two contiguous fins, whereby to prevent peripheral creeping of the bristles about the core and annular end plates disposed upon the ends of the core to prevent longitudinal displacement of the laminations, the ends of said core being outwardly ared toretain the annular end plates.

4. A rotary brush comprising a substantially cylindrical tubular core having a series of peripherally spaced longitudinal fins, a series of brush sections disposed upon the core, each section comprising a retaining ring, disposed upon the tins, double ended ybrush bristles having their tip portions projecting radially outwardly and their mid portions looped about the retaining ring to form an annular bristle lamination in which the outer bristles of the lamination contact with the corresponding bristle of contiguous laminations substantially from their looped portions to their tips, the looped portions of the bristles of each annular lamination being disposed between the fins and being grouped by the fins into segments extending peripherally of the ring, the looped portions of the bristles in the ends of the segments being in direct contact with a side of eachof the two contiguous tins, whereby to prevent peripheral creeping of the bristles about the cor'e and annular end plates secured upon the core to prevent longitudinal displacement of the laminations, said core being castellated,y and the castellations being outwardly ared to retain the annular end plates.

5. A rotary brush having a core comprising a tube having a series of peripherally spaced longitudinally extending tins extending radially therefrom and being replicately folded, longitudinally extending segments ofthe tube, a

series' ofV brush. sections disposedI upon the` core, each section comprising a retaining ring disposed upon the ns dou-ble" ended brush bristles having their tip portions pro-V jecting radially outwardly and their mid portions being looped about the retaining ring to form a bristle lamination in which the outer bristles of the lamination contact with corresponding bristles of contiguous laminations substantially from their looped portions to their tips, the looped portions of the bristles of the annular lamination lacing disposed between the fins and being grouped by the tins into segments extending peripherally of the corresponding ring, the looped portions of the bristles in the ends of the segments being in direct contact with a side of each of the two contiguous tins whereby to prevent peripheral creeping of the bristles about the core.

6. A rotary brush having a core adapted to be disposed upon a mandrel and comprising a tube having a series of peripherally spaced longitudinally extending tins` extending radially therefrom and being replicately folded, lon-` gitudinally extending segments of the tube, a series of brush sections disposed upon the core, each comprising a retaining ring disposed upon the tins, double ended brush bristles having their tip portions projecting radially outwardly and their mid portions being looped about the retaining ring to form a bristle lamination in which the outer bristles of the lamination contact with corresponding bristles of the contiguous laminations substantially from their looped portions to their tips, the looped portions of the bristles of the annular lamination being disposed between the fins and being grouped by the tins into segments extending peripherally of the corresponding ring, the looped portions of the bristles in the ends of the segments being in direct contact with a side of each of the two contiguous tins whereby to prevent peripheral creeping of the bristles about the core, said tube having castellations at the ends thereof and annular end plates upon the ends of the tube, the castellations being doubled over to retain the end plates and further being adapted to intermesh with castellations upon a contiguous member upon said mandrel to provide a positive drive.

7. A rotary brush comprising at least two brush units disposed upon a common mandrel, each unit comprising a tubular core having a series of peripherally spaced, 1ongitudinally extending, radial tins thereupon, a series of brush sections disposed upon the core, each section comprising a retaining ring disposed upon the tins, double ended brush bristles having their tip portions projecting radially outwardly and their mid portions being looped about the retaining ring to form a bristle lamination in which the outer bristles of the lamination contact with corresponding bristles of the contiguous lamination substantially from their looped portions to their tips, the looped portions of the bristles of the annular lamination being disposed between the tins and being grouped by the ns into segments extending peripherally of the corresponding ring, the looped portions of the bristles in the ends of the segments being in direct Contact with a side of each of the two contiguous fins, whereby to prevent peripheral creeping of the -bristles about the core, said tube having castellations at the ends thereof and annular end plates' upon the ends of the tube, the castellations beingV doubled over to retain the end plates, the castellations upon an end of one tube being meshed with the castellations upon the contiguous end of the second tube whereby `to provide a positive drive between the tubes.

References Cited in the tile of this patent UNITED STATES PATENTS 553,402 Goulding lan. 21, 1896 1,054,160 Abbott Feb. 25, 1913 1,240,604 Rasmesen Sept. 18, 1917 1,714,137 Radinse May 21, 1929 2,324,272 Anderson July 13, 1943 2,409,309` Peterson Oct. 15, 1949 UNITED STATES PATENT OFFICE CERTIFICATE 0E CORRECTION Patent No. 2, 824,327

William C; yVan Clief, JI,

1t is heIebST certified that error appears in the-printed specification of the above "numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4, line 49, -Joeore "Serial" insert e filed this day m3 column 6, line 23, for read As w.,

Signed and sealed this 26th day o August 1958,

(SEAL) Attest: n

KARL H. AXLINE Attesting OIcer ROBERT C. WATSON Commissioner of Patents February 25, 1958VV 

